Marine missiles for destruction of submarine targets

ABSTRACT

1. A self-propelled marine missile with an impact detonator for the destruction of a movable submarine target by dive launching in straight line toward said target, comprising, in combination, an adjustable elevator carried by the missile for dive steering said missile, means housed within the missile and connected to said elevator for adjusting the latter with respect to the missile, adjustable means accessible externally and connected to said adjusting means for controlling the latter and adjustable at the launching time for determining a constant dive angle of the missile equal to the angle of negative elevation in depth of the submarine target as detected at said launching time whereby the adjusted elevator maintains the path of the dive launched missile substantially coincident with the detected line of negative elevation of said submarine target; an assembly housed within the missile comprising an explosive charge, the impact detonator of said charge a distance responsive detonator in contacting engagement with said charge, and means for detonating the latter means impact of said missile against the submarine target; means housed within the missile for maintaining said detonating means in an inoperative position at the launching time, an adjustable means housed within the missile and responsive to the distance travelled by the missile along the path thereof for releasing said maintaining means in order to obtain an immediate operation of said detonating means, means housed within the missile for adjusting said releasing means at the launching time to operate the release of the maintaining means upon travelling a distance equal to that of the movable submarine target as detected at the launching time, and means connected to said last adjusting means, for remotely controlling the latter in accordance with said detected distance and disconnectable from said last adjusting means when the missile is dive launched.

United States Patent [191 Kahn [ 1 MARINE MISSILES FOR DESTRUCTION OF SUBMARINE TARGETS [76] Inventor:

[22] Filed:

Louis Lazare Kahn, 102, rue de Grenelle, Paris, France Sept. 27, 1956 [2]] Appl. No.: 612,517

[56] References Cited UNITED STATES PATENTS 470,286 3/1892 Canet 89/37 X 1,296,328 3/1919 Shonnard. ll4/20 1,379,972 5/1921 Fiske 114/20 2,398,801 4/1946 Minkler 114/20 2,382,593 8/1945 Wires 114/20 2,409,169 10/1946 Whittaker 114/20 2,411,156 11/1946 Grimminger... 114/20 2,417,768 3/1947 Leonard 114/25 2,419,164 4/1947 Putnam et a1 114/20 2,537,929 l/l95l Daly et a1. 114/25 2,615,416 10/1952 Daly et a1. 114/23 2,706,957 4/1955 Hughes 114/20 2,996,027 8/1961 Cooke 114/26 Primary Examiner-Benjamin A. Borchelt Assistant Exa minerThomas H. Webb ArtorneyWaters, Roditi and Schwartz EXEMPLARY CLAIM l. A self-propelled marine missile with an impact detonator for the destruction of a movable submarine target by dive launching in straight line toward said target, comprising, in combination,

[111 3,779,194 1 Dec. 18,1973

an adjustable elevator carried by the missile for dive steering said missile, means housed within the missile and connected, to said elevator for adjusting the latter with respect to the missile, adjustable means accessible externally and connected to said adjusting means for controlling the latter and adjustable at the launching time for determining a constant dive angle of the missile equal to the angle of negative elevation in depth of the submarine target as detected at said launching time whereby the adjusted elevator maintains the path of the dive launched missile substantially coincident with the detected line of negative elevation of said submarine target; an assembly housed within the missile comprising an explosive charge, the impact detonator of said charge a distance responsive detonator in contacting engagement with said charge, and means for detonating the latter means impact of said missile against the submarine target; means housed within the missile for maintaining said detonating means in an inoperative position at the launching time, an adjustable means housed within the missile and responsive to the distance travelled by the missile along the path thereof for releasing said maintaining means in order to obtain an immediate operation of said detonating means, means housed within the missile for latter in accordance with said detected distance and disconnectable from said last adjusting means when the missile is dive launched.

10 Claims, 12 Drawing Figures- PMENTEU DEC 1 8 I973 sum inr 4 Hz a PAIENIEU an: 18 ms SHEET 2 OF 4 PATENTEB um 18 1913 v SHEET 30? 4 MARINE MISSILES FOR DESTRUCTION F SUBMARINE TARGETS The present invention relates to a missile of the torpedo type more particularly suitable for the destruction of submarine targets which are located by any known spotting device adapted to determine the azimuth, the angle of elevation, and the distance of targets.

However precise the methods of target location which are used may be, for example acoustic locating methods, the factor of probability for the assailant to reach the target is very small with the projectiles used up to now, such as depth charges, shells, or the like, since the submarine enemy is capable of evasive action in an unforeseeable manner so as to escape during the interval between the spotting and the explosion of the missile. The above consideration has led to the present invention.

The main object of the present invention is to provide in an automotive marine missile for the destruction of submarine targets, means for guiding said missile along a line directed towards the target as located at the launching time, and, in addition to the usual impact detonator, a device for initiating the explosion without impact and means for controlling said device as soon as the launched missile substantially attains the location occupied bythe moving submarine target at the time of launching the missile. Said controlling means may'be actuated under the direct or indirect dependance of the distance travelled by the missile dive-launched towards the moving submarine target. The latter device may consist either of an adjustable clockwork, or of an adjustable mechanism the operation of which depends on the distance travelled by the missile.

The missile is dive-launched in the direction of the location of the submarine target as determined by the spotting device at the launching time, and it explodes a short time after launching, at the preset distance, whether or not an impact on the submarine target takes place, the latter inevitably being at this time, wholly or partially, within the range of the explosion.

To enable a rapid and accurate dive-launching, it is convenient to mount the launching tube on a revolving turret, instead of providing a fixed tube on the ship and manoeuvring the latter. Therefore, the invention also includes one or more launching tubes mounted on a turret and the axis of which is slightly dive inclined to provide for a proper and reboundless penetration of the missile into the water.

For a better understanding of the invention, embodiments thereof will now be described more fully by way of examples with reference to the accompanying drawings, in which FIG. 1 is a diagrammatical axial section of a submarine missile assembly according to the invention, with supplemental means for adjusting the exploding dis- FIGS. 8 and 9 are respectively elevational and plan views of a revolving turret equipped with three missilelaunching tubes.

FIG. 10 is a view similar to FIG. 2 ofa submarine missile assembly according to the invention, with supplemental means for adjusting the exploding distance according to a second embodiment and an angle-of-divecontrolling device similar to that shown in FIGS. to

FIG. 1 1 is a view similar to FIG. 2 ofa submarine missile assembly according to the invention, with supplemental means for adjusting the exploding distance and an angle-of-dive-controlling device according to other embodiments.

FIG. 12 is a view similar to the front part of FIG. 1 of a submarine missile assembly according to the invention, with a supplemental magnetic firing means.

The automotive missile shown in FIG. 1 comprises, in a well-known manner, a compressed air storage chamber 1, a housing 2 for accomodating the power plant (not shown) and the auxiliaries thereof, a housing 3 for accomodating the control and adjustment means, such as the direction-controlling gyroscope and the servo-motor interposed between said gyroscope and the vertical rudder, a tail section 4 including the propeller 5, the vertical rudder and the elevator and, in front, an explosive charge 6 with an impact detonator 7.

According to the invention, as illustrated in FIG. 1 the detonator 7 is provided with a supplemental striker (percussion pin) 8 which initiates the firing under the action of a spring 9 as soon as the-cable 10 to which said striker is tied is released to allow the spring to expand in its housing tube 12 extending through the explosive charge 6. The cable 10 passes through a tube 11 extending through the storage chamber 1 and through the tube 12.

The cable 10 is released by a cam device when the missile has travelled a predetermined distance for which said device has been set according to the readings of the submarine target spotting device. In the illustrated example, the device for setting the distance at which the explosion takes place operates as a counter of the revolutions of the propelling means and is arranged as will be now described (FIGS. 2 to 4).

The shaft 13.0f the propeller. 5 carries a worm 14 meshing with a gear wheel 15 which through another reducing worm gear 16, 17 drives a shaft 18 parallel to the shaft 13. On said shaft 18 is mounted, through the intermediary of a free-wheel mechanism, a triggering cam 19 which is fixedly secured to a shaft 20 aligned with the shaft 18 and projecting outside the missile into a recess 21 formed by the wall of said torpedo, sealing means being provided where said shaft 18 passes through the wall. The end of the shaft 20 is formed with a square hole wherein may be engaged the square end 23 of a remote control flexible shaft 22. The shaft 20 is also provided with an index 24 movable in front of a dial 25 for hand adjustment.

The contour of the cam 19 is circular and centered on the axis of the shaft 18, but for a notch 26. Said contour is engaged by a roller 27 carried by one end 28 (FIG. 4) of a crank lever 29 pivoted about a pin 30 secured to the shell of the missile. At the other end 31 of said lever is attached the rear end of the cable 10.

As the length of the circumference of the cam 19 corresponds, subject to the gear ratio, to the greatest launching distance contemplated, it is clear that the pin 8 will automatically initiate the explosion at the distance corresponding to the angular setting of the cam 19 with respect to the shaft 18. At the launching time, the flexible shaft 22 is torn off the missile, in a wellknown manner.

The embodiment illustrated in FIG. 10 differs from that shown in FIGS. 1 to 4 only in that shaft 13 and gears 14, 15 and 16 are replaced by a clockwork mechanism 50 adjusted according to the velocity of the missile and which directly controls the cam 19a similar to cam 19. The control shaft 51 of said clockwork mechanism projects outside the missile into a recess 21a formed by the wall of said missile, the end of said shaft being formed with a square hole wherein may be engaged the square end 23a of a remote control flexible shaft 22a. The other members which are similar to those of the assembly illustrated in FIGS. 1 to 4 have the same reference numerals followed by the index a. The pin connected to the cable 10a will automatically initiate the explosion at the distance corresponding to the angular setting of the cam 19a under the action of the clockwork mechanism 50.

Instead of being connected with the propeller, the device illustrated in FIGS. 1 to 4 may be operated by a log 52 independent from said propeller, as illustrated in FIG. 11 wherein the elements similar to those 'of said FIGS. 1 to 4 have the same reference numerals followed by the index b. Said log 52 is disposed on the outer side of the rear housing 3b and is therefore located in the horizontal projectionof the greatest crosssectional area of the missile. Said log is connected by gears 53 and 54 to a shaft 55 which through a reducing worm gear 16a, 17a drives the shaft 18b on which is mounted the cam 19b similar to cam 19 and the angular setting of which is effected by means of devices similar to those which are utilized for effecting the angular setting of cam 19.

In the embodiment illustrated in FIG. 12 which is a modification of that shown in FIGS. 1 to 4, the impact detonator 7c is further associated with a supplemental magnetic firing device 56 of any conventional type which automatically initiates the explosion without impact under the action of the distortions of the magnetic field in the proximity of the moving target within the range of efficiency of the missile charge 6c.

The adjustment of the angle of dive and the automatic control of the elevator of the torpedo according to said angle are made by means of a pendulum 32 (FIGS. 5 and 10) which may impart oscillations to a shaft 33 through a forked crank 34. Said pendulum, pivoted about an axis 35 which extends transversely to the axis of the missile, operates the conventional slidevalve of the conventional servo-motor 57 connected by the shaft 63 to the elevator in the same way as the known pendulum-piston of the hydro-valve of a conventional torpedo.

It is well known that in a conventional torpedo the pendulum controls the slide-valve of the servo-motor which in turn controls the elevator so that as long as the axis of the torpedo remains horizontal said slide-valve is closed and therefore the servo-motor is stopped, while, if said axis tends to keep an inclination with respect to the horizontal line, the pendulum opens said slide-valve in order to move said elevator, under the action of said servo-motor then operative, to restore the horizontal position of said axis.

The adjustment of the position of the pendulum at which the shaft 33 will close the slide-valve for stopping the servo-motor in order to maintain the elevator substantially parallel to the dive-launching direction, i.e., to the axis of the dive-launched missile. (i.e., the mean position of the oscillation) is made by means of an angularly adjustable connection between the shaft 33 and the crank 34 (FIGS. 6, 7 and 10). The shaft 33 is fast with a grooved disc 36 on which passes a cable 37 provided with a return spring 38; said disc carries a spring loaded latch-pin 39 which may engage any chosen one of holes 40 circumferentially spaced in a second disc 41 keyed to the shaft 33a of the crank 34, the shafts 33 and 33a being separated but aligned with each other.

For setting the angle of dive, it is only necessary, after having withdrawn, by pulling a cable 42, the latch-pin 39 from the hole wherein it was engaged, to turn the disc 36 with respect to the disc 41 by means of the cable 37 to the selected position corresponding to the dive line directed to the submarine target as located at the launching time. Therefore when the missile is divelaunched along said dive line the pendulum 32 maintains the slide-valve of servo-motor 57 in closed position while the missile elevator is substantially parallel to the missile axis directed along said dive line. If said axis tends to diverge from its launching direction the pendulum 32 controls said servo-motor 57 which by means of shaft 63 causes said elevator to diverge from its initial position in order to restore the missile axis to its initial inclination along the dive-launching line. Through suitable guiding means both cables 37 and 42 may be brought to be parallel to the axis of the missile so as to provide for a remote control similar to that of the explosion timing device.

In the embodiment illustrated in FIG. 11, the adjustment of the angle of dive and the automatic control of the elevator of the torpedo according to said angle are made by means of a gyroscope of the conventional Whitehead type with a turbine 58 adapted, in the well known manner, to drive the rotor of said gyroscope and to be disconnected from said rotor 59 at a determined time after the starting of said rotor, for example at 0.4 second from said starting. In the present utilization said rotor at rest is horizontal and mounted on a vertical gimbal 60 and a horizontal gimbal 61 the support 61a of which is connected to a forked crank 34b similar to forked crank 34 of FIG. 5 by means of a control member 62 and which controls the slide-valve of the conventional servo-motor 57b. The other elements similar to those illustrated in FIGS. 5, 6 and 10 have the same reference numerals followed by the index b. At the launching time the axis of rotor 59 is inclined according to the dive line directed to the submarine target as detected as said launching time, by means of discs 41b and 36b. Then the turbine 58 is started, drives said rotor 59 and is disconnected therefrom at the determined time. The gyroscope controls the elevator of the missile through the servo-motor as the pendulum 32 in the embodiment of FIGS. 5 and 10.

FIGS. 8 and 9 show three missile-launching tubes 43 mounted together on a revolving turret 44. Their axes are slightly inclined with respect to the plane of said turret. Said turret is rotary driven by means of any known engine to be directed in the azimuth of the target as located at the shooting time.

Of course, without departing from the scope of the invention as defined in the appended claims, modifications may be made in the illustrated embodiment described above.

What I claim is 1. A self-propelled marine missile with an impact detonator for the destruction of a movable submarine target by dive launching in straight line toward said target, comprising, in combination, an adjustable elevator carried by the missile for dive steering said missile, means housed within the missile and connected to said elevator for adjusting the latter with respect to the missile, adjustable means accessible externally 2nd connected to said adjusting means for controlling the latter and adjustable at the launching time for determining a constant dive angle of the missile equal to the angle of negative elevation in depth of the submarine target as detected at said launching time whereby the adjusted elevator maintains the path of the dive launched missile substantially coincident with the detected line of negative elevation of said submarine target; an assembly housed within the missile comprising an explosive charge, the impact detonator of said charge a distance responsive detonator in contacting engagement with said charge, and means for detonating the latter means impact of said missile against the submarine target; means housed within the missile for maintaining said detonating means in an inoperative position at the launching time, an adjustable means housed within the missile and responsive to the distance travelled by the missile along the path thereof for releasing said maintaining means in order to obtain an immediate operation of said detonating means, means housed within the missile for adjusting said releasing means at the launching time to operate the release of the maintaining means upon travelling a distance equal to that of the movable submarine target as detected at the launching time, and means connected to said last adjusting means, for remotely controlling the latter in accordance with said detected distance and disconnectable from said last adjusting means when the missile is dive launched.

2. A marine missile, according to claim 1, wherein the means for adjusting the elevator and for controlling said adjusting means, a servo-motor operatively connected to said elevator, means sensitive to the constant dive angle of the missile position for stopping said servo-motor, an adjustable connection interconnecting said stopping means and said servo-motor, and means for adjusting said connection in accordance with the angle of negative elevation of the target as detected at the launching time.

3. A marine missile, according to claim 2, wherein the means sensitive to the constant dive angle of the missile comprise a pendulum, a shaft pivotally carrying said pendulum and directed transversely to the axis of the missile, and an element carried by said. pendulum and operatively connected to control the adjustable connection.

4. A marine missile, according to claim 2, wherein the means sensitive to the constant dive angle of the missile comprise, a gyroscope having a rotor, the axis of which is vertical at rest, two gimbals pivotally supporting said rotor, and including an inner one which is vertical and an outer one which is horizontal, power means for rotatably driving said rotor, and an element carried by the outer horizontal gimbal and, operatively connected to control the adjustable connection.

5. A marine missile, according to claim 2 wherein the adjustable connection and the means for adjusting said connection comprise a forked crank the fork of which engages a part of the stopping means, a disc keyed on the pivot of said forked crank and formed with circumferentially spaced holes, a shaft aligned with the pivot of said forked crank, a connection between said shaft and the servo-motor, a grooved disc keyed on said shaft, a spring-loaded latch-pin carried by said grooved disc and adapted to engage one of the holes of the first disc, a control cable connected to said latch-pin, a selecting cable passing round said grooved disc for-selecting the position thereof with respect to the first disc, and a return spring connected to said selectingcable.

6. A marine missile, according to claim 1, wherein the means for detonating the distance responsive, detonator and for maintaining said detonating means in an inoperative position comprise a firing pin housed within the missile in contacting engagement with the distance responsive detonator thereof, aspring adapted to push said firing pin by expansion against said detonator, a cable connected to said firing pin for maintaining the same against the action of said spring, and a trigger device comprising a crank lever having one end connected to said cable, a pin perpendicular to the axis of v the missile, secured to the shell of the missile and on which said crank lever is pivotally mounted, a roller pivotally mounted on the other end of said crank lever, acircular cam formed with a radial notch and the contour of which is engaged by said roller, and a shaft parallel to the axis of the missile, connected to the controlling means and carrying said cam.

7. A marine missile according to claim 6, wherein the cam carrying shaft projects outside the missile and wherein the means for releasing the maintaining means and for adjusting said releasing means comprise a worm carried by the propeller shaft of the missile, a shaft aligned with the cam-carrying shaft, a freewheel mechanism interposed between said shaft and the cam, transmission means interconnecting said shaft and said worm, a remote control flexible device engaging the outer projection of said cam-carrying shaft in a disengageable manner, an index carried by said projection, and a dial in front of which said index is displaced for hand adjustment.

8. A marine missile according to claim 6, wherein the means for releasing the maintaining means and for adjusting said releasing means comprise a clock work mechanism operatively connected to the cam-carrying shaft and having a control shaft which projects outside the missile, a remote control flexible device engaging the outer projection of said control shaft in a disengageable manner, an index carried by said projection, and a dial in front of which said index is displaced for hand adjustment.

9. A marine missile according to claim 6, wherein the means for releasing the maintaining means and for adjusting the releasing means comprise a log pivotally mounted on the rear part of the missile and contained in the projection of the greatest cross-sectional area of said missile, a shaft aligned with the cam-carrying shaft, a free-wheel mechanism interposed between said shaft and the cam, and transmission means interconnecting said shaft and said log.

10. In a self-propelled marine torpedo, a device for attacking a moving submerged target at a distance and along a line of negative elevation which are detected responsive to distance travelled by the missile, and adjustable means accessible externally of the missile for setting the firing means prior to launching the missile to respond to travel of the missile a distance equal to the detected distance of the target from the surface location of attack, thereby to detonate the charge in the immediate vicinity of the detected target location in the absence of impact therewith. 

1. A self-propelled marine missile with an impact detonator for the destruction of a movable submarine target by dive launching in straight line toward said target, comprising, in combination, an adjustable elevator carried by the missile for dive steering said missile, means housed within the missile and connected to said elevator for adjusting the latter with respect to the missile, adjustable means accessible externally 2nd connected to said adjusting means for controlling the latter and adjustable at the launching time for determining a constant dive angle of the missile equal to the angle of negative elevation in depth of the submarine target as detected at said launching time whereby the adjusted elevator maintains the path of the dive launched missile substantially coincident with the detected line of negative elevation of said submarine target; an assembly housed within the missile comprising an explosive charge, the impact detonator of said charge a distance responsive detonator in contacting engagement with said charge, and means for detonating the latter means impact of said missile against the submarine target; means housed within the missile for maintaining said detonating means in an inoperative position at the launching time, an adjustable means housed within the missile and responsive to the distance travelled by the missile along the path thereof for releasing said maintaining means in order to obtain an immediate operation of said detonating means, means housed within the missile for adjusting said releasing means at the launching time to operate the release of the maintaining means upon travelling a distance equal to that of the movable submarine target as detected at the launching time, and means connected to said last adjusting means, for remotely controlling the latter in accordance with said detected distance and disconnectable from said last adjusting means when the missile is dive launched.
 2. A marine missile, according to claim 1, wherein the means for adjusting the elevator and for controlling said adjusting means, a servo-motor operatively connected to said elevator, means sensitive to the constant dive angle of the missile position for stopping said servo-motor, an adjustable connection interconnecting said stopping means and said servo-motor, and means for adjusting said connection in accordance with the angle of negative elevation of the target as detected at the launching time.
 3. A marine missile, according to claim 2, wherein the means sensitive to the constant dive angle of the missile comprise a pendulum, a shaft pivotally carrying said pendulum and directed transversely to the axis of the missile, and an element carried by said pendulum and operatively connected to control the adjustable connection.
 4. A marine missile, according to claim 2, wherein the means sensitive to the constant dive angle of the missile comprise, a gyroscope having a rotor, the axis of which is vertical at rest, two gimbals pivotally supporting said rotor, and including an inner one which is vertical and an outer one which is horizontal, power means for rotatably driving said rotor, and an element carried by the outer horizontal gimbal and operatively connected to control the adjustAble connection.
 5. A marine missile, according to claim 2 wherein the adjustable connection and the means for adjusting said connection comprise a forked crank the fork of which engages a part of the stopping means, a disc keyed on the pivot of said forked crank and formed with circumferentially spaced holes, a shaft aligned with the pivot of said forked crank, a connection between said shaft and the servo-motor, a grooved disc keyed on said shaft, a spring-loaded latch-pin carried by said grooved disc and adapted to engage one of the holes of the first disc, a control cable connected to said latch-pin, a selecting cable passing round said grooved disc for selecting the position thereof with respect to the first disc, and a return spring connected to said selecting cable.
 6. A marine missile, according to claim 1, wherein the means for detonating the distance responsive, detonator and for maintaining said detonating means in an inoperative position comprise a firing pin housed within the missile in contacting engagement with the distance responsive detonator thereof, a spring adapted to push said firing pin by expansion against said detonator, a cable connected to said firing pin for maintaining the same against the action of said spring, and a trigger device comprising a crank lever having one end connected to said cable, a pin perpendicular to the axis of the missile, secured to the shell of the missile and on which said crank lever is pivotally mounted, a roller pivotally mounted on the other end of said crank lever, a circular cam formed with a radial notch and the contour of which is engaged by said roller, and a shaft parallel to the axis of the missile, connected to the controlling means and carrying said cam.
 7. A marine missile according to claim 6, wherein the cam carrying shaft projects outside the missile and wherein the means for releasing the maintaining means and for adjusting said releasing means comprise a worm carried by the propeller shaft of the missile, a shaft aligned with the cam-carrying shaft, a free-wheel mechanism interposed between said shaft and the cam, transmission means interconnecting said shaft and said worm, a remote control flexible device engaging the outer projection of said cam-carrying shaft in a disengageable manner, an index carried by said projection, and a dial in front of which said index is displaced for hand adjustment.
 8. A marine missile according to claim 6, wherein the means for releasing the maintaining means and for adjusting said releasing means comprise a clock work mechanism operatively connected to the cam-carrying shaft and having a control shaft which projects outside the missile, a remote control flexible device engaging the outer projection of said control shaft in a disengageable manner, an index carried by said projection, and a dial in front of which said index is displaced for hand adjustment.
 9. A marine missile according to claim 6, wherein the means for releasing the maintaining means and for adjusting the releasing means comprise a log pivotally mounted on the rear part of the missile and contained in the projection of the greatest cross-sectional area of said missile, a shaft aligned with the cam-carrying shaft, a free-wheel mechanism interposed between said shaft and the cam, and transmission means interconnecting said shaft and said log.
 10. In a self-propelled marine torpedo, a device for attacking a moving submerged target at a distance and along a line of negative elevation which are detected from a surface location of attack, said device comprising: dive angle control means on the missile, adjustable means accessible externally of the missile for setting the dive angle control means prior to launching the missile in the dive-direction of the detected target to determine a sustained dive angle of the missile corresponding to the detected angle of negative elevation of the target with respect to the surface location of attack an explosive charge in the missile, the impact detonator oF said charge firing means for detonating the charge responsive to distance travelled by the missile, and adjustable means accessible externally of the missile for setting the firing means prior to launching the missile to respond to travel of the missile a distance equal to the detected distance of the target from the surface location of attack, thereby to detonate the charge in the immediate vicinity of the detected target location in the absence of impact therewith. 